Patek Philippe self-winding flyback chronograph with Annual Calendar Reference 5905/1A-001
		
	
	
	
       
                
Patek Philippe self-winding flyback chronograph with Annual Calendar Reference 5905/1A-001
       
	 
 
Patek Philippe introduces three new versions of chronographs with additional complications 
 
The chronograph has always played a leading role amid the vast repertoire of Patek Philippe complicated watches. Since 2005, the Manufacture has confirmed this mastery by developing a complete range of chronograph movements, with or without additional functions, entirely designed and crafted in its workshops.
The starting point was caliber CHR 27-525 PS, the world’s thinnest split-seconds chronograph movement presented in 2005.
 
Introduced in 2006, caliber CH 28-520 – the second 
“in-house’” chronograph movement – features automatic winding, a modern vertical disk-type clutch system, a flyback function, a large single counter at 6 o’clock and a chronograph seconds hand that can be used as a permanent (running) seconds hand. It can be combined with additional complications, as is the case with the two new models: 5905/1A (chronograph and Annual Calendar) and 5930P (chronograph and World Time).
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Launched in 2009, caliber CH 29-535 PS – the third exclusive chronograph movement – combines traditional architecture (manual winding, column wheel, toothed-wheel horizontal clutch system) with six patented innovations. In the current collection, it powers a men’s model (Reference 5172) and a ladies’ model (Reference 7150/250). In 2011, this base caliber was interpreted in a Grand Complication version incorporating a perpetual calendar (CH 29-535 PS Q), present on the 5270 and 5271 models. Since 2012, it can also be found on Reference 5204 in a split-seconds chronograph and perpetual calendar version (CHR 29-535 PS Q).
 
The various Patek Philippe chronograph calibers are offered in the current collection in more than 20 variations – to which three new, resolutely contemporary interpretations have now been added.
 
Patek Philippe 
self-winding flyback chronograph 
with Annual Calendar 
 
Launched as a platinum model in 2015, then in rose gold in 2019, Reference 5905 combines two practical and easy-to-use complications: a self-winding flyback chronograph and a patented Annual Calendar. The Manufacture is reinterpreting the style of this much sought-after model by unveiling a first version in steel – a rare metal in the Patek Philippe collections – with a three-link integrated bracelet. This bold and casual design renews the way a Patek Philippe complication watch is worn on a daily basis. 
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The extremely rhythmical dial features a new elegant and contemporary sunburst olive green color. It ensures excellent legibility for the additional functions, with a central chronograph hand, a large 60- minute subdial at 6 o’clock and three day/date/month apertures arranged in an arc for instant reading of the Annual Calendar indications. There is also a discreet day/night indicator at 6 o’clock that is useful for ensuring accurate date setting.
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Visible through the transparent sapphire caseback, caliber CH 28-520 QA 24H remains faithful to the traditional column wheel for the transmission of chronograph commands. However, instead of a toothed-wheel horizontal clutch, it has a vertical disk-type clutch. This modern technical solution causes almost no wear and tear, and the central chronograph seconds hand can also be used as a permanent (running) seconds display. The patented Annual Calendar automatically takes account of 30- and 31-day months, requiring only one correction per year, on March 1
st. 
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The polished steel case features a sophisticated construction with a concave bezel and recessed sides. The integrated steel bracelet is inspired by that of the Aquanaut Reference 5167/1A with its contrasting finishes (polished outer links and satin-finish inner links), while subtly distinguished from it by the underside of the bracelet and the edges which are polished, in line with the case. It is equipped with a patented Patek Philippe fold-over clasp secured by four independent catches.
 
The new Reference 5905/1A-001 is joining existing References 5905P-001 in platinum with a blue dial and 5905R-001 in rose gold with brown dial.